#ifndef CALCULATOR_H
#define CALCULATOR_H

#include <string>

class Calculator
{
public:
    static Calculator& getInstance();

    double getValue(const std::string &input);

private:
    Calculator(){}
    ~Calculator(){}
    Calculator(const Calculator &r);
    Calculator& operator=(const Calculator &r);

    int getPriority(char c);
};

#endif // CALCULATOR_H
